Fingerprinting of egg and oil binders in painted artworks by matrix-assisted laser desorption ionization time-of-flight mass spectrometry analysis of lipid oxidation by-products

• Published in: Analytical and bioanalytical chemistry 2011-06, Vol.400 (7), p.2229-2240
• Main Authors: Calvano, C. D., van der Werf, I. D., Palmisano, F., Sabbatini, L.
• Format: Article
• Language: English
• Subjects: Analytical Chemistry; Binders; Biochemistry; Byproducts; Characterization and Evaluation of Materials; Chemical properties; Chemistry; Chemistry and Materials Science; Exact sciences and technology; Food Science; Ionization; Laboratory Medicine; Lasers; Lipids; Markers; Monitoring/Environmental Analysis; Original Paper; Oxidation-reduction reaction; Spectrometric and optical methods; Spectrum analysis; Tags
• ISSN: 1618-2642; 1618-2650
• DOI: 10.1007/s00216-011-4919-1

A matrix-assisted laser desorption ionization time-of-flight mass spectrometry-based approach was applied for the detection of various lipid classes, such as triacylglycerols (TAGs) and phospholipids (PLs), and their oxidation by-products in extracts of small (50–100 μg) samples obtained from painted artworks. Ageing of test specimens under various conditions, including the presence of different pigments, was preliminarily investigated. During ageing, the TAGs and PLs content decreased, whereas the amount of diglycerides, short-chain oxidative products arising from TAGs and PLs, and oxidized TAGs and PLs components increased. The examination of a series of model paint samples gave a clear indication that specific ions produced by oxidative cleavage of PLs and/or TAGs may be used as markers for egg and drying oil-based binders. Their elemental composition and hypothetical structure are also tentatively proposed. Moreover, the simultaneous presence of egg and oil binders can be easily and unambiguously ascertained through the simultaneous occurrence of the relevant specific markers. The potential of the proposed approach was demonstrated for the first time by the analysis of real samples from a polyptych of Bartolomeo Vivarini (fifteenth century) and a “French school” canvas painting (seventeenth century).